The P. gingivalis polysaccharide was analyzed for monosaccharide composition by preparing the TMS derivatives of the methylglycosides followed by GC and combined GC/MS analyses. TMS methylglycosides were prepared from the sample by methanolysis in 3 M HCl in methanol, followed by N-acetylation with pyridine and acetic anhydride. The methanolysis and N-acetylation steps were then repeated and the samples treated with Tri-Sil. GC analysis of the TMS methylglycosides was done on an HP 5890 GC using a DB1 fused silica capillary column. GC/MS analysis was performed using a Hewlett Packard 5890 GC coupled to a 5970 MSD. Monosaccharides were identified by their retention times in comparison to standards, and their carbohydrate character was authenticated by their mass spectra. Additionally, the identity of an unusual sugar component was investigated by performing GC/CI-MS.